Preparation method of LiFePO4/C composite materials

The invention discloses a preparation method of LiFePO4/C composite materials, comprising the following steps of mixing and ball milling raw materials to form a sizing agent, then adding citric acid as a dispersion medium and a carbon source, stirring uniformly through a magnetic stirrer, placing for a while at a certain temperature to form a precursor, and then high sintering at the protective atmosphere to obtain the LiFePO4/C composite materials with fine grains. The prepared LiFePO4/C composite materials have the same crystalline phase structure as the pure phase LiFePO4/C materials. The raw materials are in the state of flowing deformation in the mixing stage, thus mixing is very uniform; at the same time, the flowing deformation phase medium is used as the carbon source, and the prepared LiFePO4/C composite materials are very pure and have fine grains. The LiFePO4/C composite materials have the fine grains and carbon coating layers, thereby having the excellent electrochemistry property, including the multiplying power property and the cyclical stability.